<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>超时调用</title>
    <script>
        function abc(){
            setTimeout(function (){
                // alert("太好了")
                document.getElementById("title").innerText = "成功了"
            },1000);
        }
    </script>
</head>
<body>
    <h1 id="title">超时调用--只调用一次</h1>
    <button onclick="abc()">点击</button>
</body>
</html>